Fuel connection to cylinder head



Sept. 24, 1968 D. C. DICKERSON ET AL FUEL CONNECTION TO CYLINDER HEAD Filed July 8, 1966 F /G. 6O

39 I .4 52 70 1Q 72 26 24 s4 26 FIG 2 82 \48 42 38 A w 4 :1 30 J 54 IG/W NVENTORS DEVERE C. DICKERSON RONAL M. BACHOR SKI llili United States Patent 3,402,703 FUEL CONNECTION T0 CYLINDER HEAD Devere C. Dickerson, Wheaton, and Ronald M. Bachorski, Glen Ellyn, Ill., assignors to International Harvester Company, Chicago, Ill., a corporation of Delaware Filed July 8, 1966, Ser. No. 563,820 Claims. (Cl. 123-32) ABSTRACT OF THE DISCLOSURE Fuel connection to cylinder head comprising a disconnectible coupling in the fuel line. The line can be broken at the coupling to avoid inconvenience. To prevent lube oil contamination, the coupling vents externally to atmosphere because of the eventuality that vibration may cause the seal in the coupling to leak, whereupon leaking fuel will harmlessly drain down the outside of the head.

This application relates to the cylinder head structure of an injection type internal combustion engine. It more particularly relates to a fuel connection mounted in a convenient manner upon such structure whereby a fuel line can be led-in to the head for supplying fuel under pressure to an associated injection nozzle.

Our invention is an improvement over US. Patent No. 3,194,221, having the objectives and advantages of the latter plus further advantages. The patent disclosure is incorporated in entirety herein by reference.

In one standard fuel injection system, a common fuel pump supplies metered charges of the fuel. Those charges are fed by fuel delivery lines leading to individual injection nozzles, from which the charges are injected, according to the cylinder firing order, into the respective engine cylinders on which such nozzles are located. The lines are led through a cylinder head cover, making it necessary to disturb the fuel delivery lines to the pump when the cover alone or when the cover and nozzles are removed.

Breaking the connections at the terminal ends of the fuel lines is a disadvantage because of the long, unwieldly lines, because of the inconvenience of the work involved, and because of disturbing the seal at the critical points of connection to the nozzle and to the pump. So conversely, it is a disadvantage when the pump is removed, which removal requires the disturbance of the terminal connections of the fuel delivery lines to the injection nozzles.

An object of the present invention is the provision, in each of the fuel lines between a common pump and individual injection nozzles, of an interposed lead-in coupling or adapter fitting located in the head wall structure and providing a convenient break-point in the line. Because the coupling serves as the break-point, it takes the Wear of repeated connections and disconnections necessary for servicing of the engine. If the nozzles are to be removed, then the cylinder head cover, the nozzles, and the inner portion (i.e., covered portion) of the fuel lines interconnecting the nozzles and their respective couplings are removed alone. If the common fuel pump is to be removed, the pump mountings are released, and the pump and the outer (i.e., exposed) portion of the fuel lines interconnecting the pump and the respective couplings are alone taken from the engine. Thus the sealed terminal connections to the pump and nozzles need not be disturbed.

Another object of the invention is to provide a wall opening which is between the outer side of the wall structure and the head chamber and which securely receives a fuel line coupling therein, and to provide in the coupling a leakage collecting chamber and a passage between an 3,402,703 Patented Sept. 24, 1968 outside face of the coupling and the leakage collecting chamber, enabling the latter to communicate through the outer side of the wall structure to atmosphere. Thus if the sealing is faulty within the fuel line coupling or a leak develops therein by reason of vibration of the engine or for other reasons, leakage fuel is readily led away without contaminating and diluting lubricating oil in the head chamber.

In one practical aspect of the invention as applied to a V-type engine, the mouth of each leakage passage in the couplings of one bank is on the inside of the V so as to face the opposite bank and thus collectively, with the other mouths, those mouths provide a series of conveniently inspected, telltale leak holes enabling the operator readily to locate poorly sealed couplings.

Further features, objects, and advantages will either be specifically pointed out or become apparent when, for a better understanding of the invention, reference is made to the following written description taken in conjunction with the accompanying drawing, which shows a preferred embodiment thereof and in which:

FIGURE 1 illustrates an engine embodying the present invention, the view as taken showing the right bank of such engine and specifically showing the head end of a cylinder thereof in transverse cross section;

FIGURES 2 and 3 are respective exploded and assembled, longitudinal sectional views through a lead-in coupling for fuel located in the head wall structure; and

FIGURE 4 is a fragmentary external view of the head viewed in the vicinity of and in the directions of the arrows IVIV appearing in FIGURE 1.

More particularly in a diesel engine 10 as illustrated in the drawing, a common fuel metering pump 12 in the fuel system discharges metered amounts of fuel under pressure, and in rotation, through outer fuel delivery lines 14 to coupling means 16 which lead through the wall structure 18 of the engine cylinder head so as to supply the individual fuel injection nozzles. Drain return fuel from the nozzles is drained through individual return lines 20, a common header, and a common coupling means 22 leading through a thick portion, not shown, of the wall structure 18. An outer drain return line 24 which is connected to the coupling means 22 returns the fuel to a fuel tank, not shown.

The coupling means 16 for supplying each nozzle comprises a chambered, bulkhead union 26, an inner, tubular fuel delivery line 32 which bottoms in the chamber in the union 26, a ferrule 28 which is wedged within a tapering portion 30 of the chambered union 26 and which carries and seals the fuel delivery line 32, and a discharge gland fitting 34 which is received in the union and clamps the ferrule 28 fluid tight thereto, and which further seals off the end of an internal chamber 36.

There is little or no change in the flow cross sectional area in the coupling means 116. The chamber 36 is defined between the interior of the union 26 and the ferrule 28, and collects leakage fuel so as not to allow it to contaminate the lubricating oil which comes from the rocker arms and which collects on a recessed face 39 of the head.

The union 26 is threaded at the reduced outer end 38 to receive the cap fitting 40 of the associated outer fuel delivery line 14, and presents a transverse outside face 42. The internal chamber 36 communicates to atmosphere through an interconnecting bleed passage 44 which intersects the face 42 to form a telltale leak hole 46.

The union 26 has a double threaded reduced portion including external threads 48 that fit a threaded opening 50 through the wall structure 18. A gasket washer 52 cooperates with the threads 48 in sealing off the opening so as to confine the lubricant and also to'avoid contamination of the lubricant within the cylinder head. A set of internal threads 54 receives the external threads of a complementary threaded portion of the gland 34. Pipe threads, or equivalent such as /2 inch internal-20 UNF-2B and /2 inch external-20 UNF-2A threads, are employed.

The views of FIGURE 1 and 4 show an engine and more specifically the head of the right bank of a V-type engine 10. The vertical central reference plane is indicated at 56 in FIGURE 1, causing the telltale leak holes 46 according to FIGURE 4 to face that plane and inwardly toward the opposed bank of cylinders, not shown. The particular embodiment shown is a 90, V-8 diesel engine, and it can be appreciated that the mouths of the holes 46 are readily observed for leaks upon looking downwardly into an engine compartment containing the engine.

The primary chamber defined by the head is a lubricant collecting valve chamber 58 having a head cover 60 on the outer side covering the chamber across its open face. The cover 60 is held in place by hold down bolts, not shown, and is sealed fluid tight upon the wall structure of the head by a flat gasket 62. Collected lubricant on the recessed, opposite face 39 of the head drains through a row of eight rod openings 64 which are individually vertically disposed in the head and through which sets of valve push rods 66 depend to a point where they are connected by tappets to a camshaft, not shown, in a lower portion of the engine 10.

The coupling means 22 in the drain return line includes a threadably disconnectible cap fitting 68 for disconnecting the inner drain return line, and a threadedly disconnectible cap fitting 70 for disconnecting the outer drain return line 24.

Each injector nozzle of the engine is enclosed in a sleeve 72 which passes through a water chamber 74 in the head and which is sealed fluid tight to the head. The numeral 76 designates one of the individual nozzles, which receives its supply of fluid through a diagonal arm 78, and discharges the slight leakage of drain return fluid through a cap fitting 80 connected to an associated inner drain return line 20.

Each nozzle 76 is controlled by an hydraulically actuated injection valve, not shown, to cyclically spray liquid fuel through one or more spray jets in a nozzle tip 82 into an engine cylinder. A piston 84 reciprocates in conventional way within the cylinder and operates on the diesel cycle.

From the foregoing, it is seen that the interposed coupling means 16 define fluid tight fuel paths communicating with the respective injection nozzles. Once installed,

the hollow bulkhead union 26 of each coupling remains securely in place in the wall structure opening 50. During disassembly, the connections of the respective tubular fuel delivery lines are broken at either the outer end portion 38 of the union or the portion which has the threads 54 provided on the inner end thereof.

Perceptible leakage noted at any of the telltale holes 46 will necessitate tightening of the gland fitting 34 or else the disassembly of it, and the associated ferrule 28 and tubing end 32, for inspection and replacement of the leakage causing component. No back pressure can accumulate in the internal chamber 36 such as might force fuel into the valve chamber 58, the reason being the atmospheric pressure always maintained due to the bleed passage 44.

What is claimed is: 1. In a cylinder head: an enclosed rocker arm chamber therein having an outer wall; a nozzle in said head having an inlet end enclosed within the chamber; fuel supply means connected to the nozzle inlet and extending through said outer wall from inside to outside of the chamber; and a coupling secured in the wall forming a connection in said fuel supply means;

,said coupling having a small chamber therein normally sealed from the flow of fuel through the fuel supply means, and a drain from the small chamber to the outside of the rocker arm chamber.

2. The invention of claim 1, characterized by said small chamber comprising a leakage collecting chamber (36).

3. The invention of claim 2, characterized by said rocker arm chamber comprising the lubricant collecting, valve chamber of the head.

4. The invention of claim 2, characterized by chamberforming head wall structure having a cover (60) at the outer side covering the rocker arm chamber across an open face, the opposite face (39) of the chamber adapted to communicate collected, valve gear lubricant to an engine crankcase.

5. The invention of claim 4, further including means (62) sealing the cover fluid tight to said wall structure.

6. The invention of claim 5, characterized by a head wall structure coupling being threaded in said opening and, together with said cover, sealing the first chamber lubricant from contaminants on the outer side.

7. The invention of claim 1, in use upon and in combination with:

a V-type engine having two cylinder heads secured one on each of the different banks of the engine;

there being at least two of said couplings disposed one on the head of each bank on the inner side of the V;

said drain leading leakage fluid in each coupling and comprising a bleed passage interconnecting the small chamber in the coupling and an outside face of the coupling so as to form a telltale leakage hole at its point of intersection with the latter; each coupling and its telltale leakage hole facing toward the central vertical reference plane of the engine in confronting relation to another coupling and leakage hole as a convenience in inspecting the engine for fuel line leaks.

8. The invention of claim 4, characterized by the coupling being formed respectively by a bulkhead union having an outside face facing away from the first rocker arm chamber, a tube-containing ferrule (28) in spaced relation within the union so as to jointly form said small chamber therewith, a discharge fitting (34) sealing the internal chamber from the first chamber and clamping the ferrule to said union, and means for leading away leakage fluid comprising a generally longitudinally extending passage (44) in the union between the outside face thereof and the small chamber whereby the latter com.- municates to atmosphere.

9. The invention of claim 8, characterized by said discharge fitting being threadably disconnectable from the union without disturbing the remainder of the injection system, said system including a tube-containing cap fitting threadably disconnectable from the union.

10. The invention of claim 8, further including, in the injection system, outer and inner nozzle drain return lines coupled by coupling means (22) so as to return nozzle drain fluid through the head wall structure, each drain return line having a cap fitting respectively threadably disconnectable from the coupling means.

References Cited UNITED STATES PATENTS 1,664,125 3/1928 Lowrey 28513 2,001,358 5/1935 Guernsey l2332 2,313,323 3/1943 Cowles 285-34l 2,326,171 8/1943 Reggio l2332 2,463,707 3/ 1949 Matousek 285341 2,548,904 4/1951 Neal et al l2332 3,034,488 5/1962 Reiners l2332 3,125,078 3/1964 Reiners l2332 3,194,221 7/1965 Dinger et al. l23-32 LAURENCE M. GOODRIDGE, Primary Examiner. 

